2. Add the following lines anywhere within the <Global> section:
# Restrict the range of ports from which the server will select when sent the
# PASV command from a client. Use IANA-registered ephemeral port range of
# 49152-65534
PassivePorts 49152 65534

3. If you are running ProFTPD in standalone mode, restart ProFTPD. No further
action is necessary if ProFTPD is called via inetd or xinetd.

Note: In our environment,
we had to make the following modifications to our IP Filter ruleset to allow
these passive FTP connections: